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Quadrature Amplitude Modulation
2019The Quadrature Modulation Scheme (QUAM) uses sine and cosine orthogonality properties to allow the transmission of two different signals in the same carrier, which occupies a bandwidth that is equivalent to the AM signal. The QUAM modulator can be assembled using two DSB-SC modulators.
Marcelo S. Alencar, Valdemar C. da Rocha
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Differential Encoding for Quadrature-Amplitude Modulation
2010 IEEE 71st Vehicular Technology Conference, 2010In this paper, we propose a novel differential encoder for QAM (quadrature-amplitude modulation), by a look-up table instead of a rule. Using a table for differential encoding has the advantages of both low complexity and good error performance. We propose algorithms to construct the table for maximizing the minimum noncoherent distance and minimizing ...
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Jointly optimized quadrature amplitude modulation
2016 IEEE International Conference on Communications (ICC), 2016Quadrature amplitude modulation has been widely used for high-speed data transmission in modern digital communication systems. In this work, a generalized quadrature amplitude modulation which relaxes the constraint of square lattice is suggested to improve the joint performance of modulation and coding.
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Synchrophasor measurement method based on quadrature amplitude modulation
2018 26th Signal Processing and Communications Applications Conference (SIU), 2018Synchrohasor measurement is a common tool to monitor system stability and detect faults in electric power systems and various Phasor Measurement Units (PMUs) have been developed for this purpose. Parameter computation methods of PMUs specifically designed for rapidly time-varying voltage cases caused by nonlinear dynamic loads have been an attractive ...
Ali Gokoglu +2 more
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Partitioned Quadrature Amplitude Modulation for Mobile Video Transmission
IEEE Sixth International Symposium on Multimedia Software Engineering, 2005This paper presents a dual priority transmission system for mobile channels suitable for mobile video applications. The transmission system is comprised of a 16 quadrature amplitude modulation (QAM) technique and channel-coding scheme. The twin class 16-QAM system is used to transport a compressed video bitstream, which is partitioned to mach the bit ...
Vasileios Theodorakopoulos +1 more
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A Novel Ternary Quadrature Amplitude Modulation
2006 2nd International Conference on Information & Communication Technologies, 2006We propose TQAM (ternary quadrature-amplitude modulation) as a scheme of modulating analog signals to carry ternary digital data. We propose a model for the constellation diagram of the new scheme. Our motivation of thinking about this issue is the fact that the application of multi-value (non-binary) digital signals can provide considerable relief of ...
A.M. Haidar, R. Dernaika, F. Shibani
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Hexagonal Quadrature Amplitude Modulation Aided Spatial Modulation
2019 11th International Conference on Electrical and Electronics Engineering (ELECO), 2019In this study, a new multiple-input multiple-output (MIMO) transmission scheme with energy-efficiency is proposed by combining spatial modulation (SM) and energy-efficient hexagonal quadrature amplitude modulation (HQAM) constellation scheme, briefly called HQAM-SM.
Fatih Cogen, Erdogan Aydin
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An exact recursive filter for Quadrature Amplitude Modulation dynamics
2008 42nd Asilomar Conference on Signals, Systems and Computers, 2008In certain models for communications signals, such as quadrature amplitude modulation (QAM), circular stochastic processes arise quite naturally. However, much of the literature concerning estimation for communications processes, such as QAM signals, is based upon Cartesian coordinate representations and approximated dynamics, subsequently amenable to ...
Robert J. Elliott, William Paul Malcolm
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A multimode adaptive beamformer for quadrature-amplitude-modulated signals
ICASSP-88., International Conference on Acoustics, Speech, and Signal Processing, 2003The authors present the results of recent work on an adaptive beamformer designed to enhance the reception of N-state quadrature amplitude modulated (N-QAM) signal in the presence of multipath distortion and cochannel interference. Adaptation of the beamformer is based on a series of performance criteria derived from known properties of the transmitted
Richard P. Gooch, Brian J. Sublett
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Robust Maximum Likelihood Classification of Quadrature Amplitude Modulation
2010 IEEE Wireless Communication and Networking Conference, 2010This paper is concerned with amplitude-based maximum likelihood classification for quadrature amplitude modulation formats in the presence of frequency offset. We first propose a simplified classification algorithm that incurs a small loss in performance.
Qinghua Shi, Yoshio Karasawa
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